Unidentified Infrared Emission Structure And Object Environment

Unidentified Infrared Emission(UIE) is widely observed in the universe,whose radiation energy accounts for about 20% of the total infrared radiation the Milky Way.However, the carrier of the UIE emission is still under debate.In the first part of our work, we searched for dozens of UIE source, which have both 3.3 ?m and 3.4 ?m emission features in the literatures. We took the spectra images from the literatures and make use of the software “Get Data Graph Digitizer”to digitize the spectra. Then we fitted all the spectra with a plateau plus several larentzian lines to account for the continuum and emission lines respectively. Based on the fitting, we get the flux ratio of the 3.4 ?m feature to the 3.3 ?m(I3.4/I3.3). Our results indicate that most UIE sources show much stronger 3.3 ?m feature than 3.4?m, with a few exceptions. We suspect this may be related to the environment of the UIE sources. Therefore, we collect all the available data related to the environment of these sources, including temperature(represent stellar hardness) and stellar intensity.We made a statistical analysis of I3.4/I3.3 and the temperature of the star that illuminate the UIE source. We find that the I3.4/I3.3 do increase with the decrease of the tempereature. Nevertheless, for HII/CHII regions, the temperature of the center stars are very close while the I3.4/I3.3 differs significantly. This suggests that the aliphatic fraction of the UIE carriers can be affected by both the temperature and the intensity of the star light.The second part of the work, we present high spatial resolution X-ray spectroscopy of supernova remnant Tycho using the Chandra observation data. We obtained maps of absorbing column density, weight-average temperature, ionization age, and the abundances for O, Ne, Mg, Si, S, and Fe, with emission measure the weight. The abundance maps and the finding that Fe abundance is not correlated with any other elements suggest that Fe locates at smaller radius than the others do,supporting the onion shell model with the emission from more massive elements peaking more toward the center. A tight correlation between Si and S abundance supports that both Si and S come from the explosive O-burning and/or incomplete Si-burning. O & Ne abundance shows no correlation with any other elements.Considering that O, Ne and Mg are all synthesized in the same process(C/Ne-burning), we suggest that O/Ne/Mg might mix well with other elements during the explosion of the SN and the expansion of the SNR. We observed a non sphericaldistribution of the nonthermal filaments in the north and west part of the SNR with respect to both the geometric center and the explosion center. This might suggest asymmetric explosion of Tycho's SN.